Hide and Seek - The Faintest Planet Ever Imaged, Pluto’s Landslides & Starlink’s 355,000 Dodges

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Welcome to Astronomy Daily, your daily


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dose of space and astronomy news. I'm


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Anna.


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>> And I'm Avery. It's Thursday, the 16th


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of July, 2026, and we have a genuinely


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lovely lineup for you today, including a


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story that's been 10 years in the


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making. Or more accurately, 10 years in


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the hiding.


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>> That's our lead. Astronomers have


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finally caught a planet that's been


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playing hideand seek with them for over


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a decade. And it turns out to be the


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faintest exoplanet ever imaged from


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Earth. And it lives in a southern


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constellation, which makes it feel just


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a little bit like ours.


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>> We've also got the completion of a


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9-year project to build the sharpest


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radio map of the entire sky and the


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James Web Space Telescope catching a


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super massive black hole in the act of


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feeding itself. Ben, it's a double bill


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from the outer solar system. Landslides


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on Pluto spotted for the first time and


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evidence that Pluto's big moon Cheron


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once spun more than 10 times faster than


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it does today.


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>> And we'll wrap the news with some


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sobering numbers. SpaceX's Starlink


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satellites had to dodge potential


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collisions more than 355,000


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times in the past year. We'll unpack


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what that means for everyone's orbit.


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plus your southern hemisphere sky


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watching for tonight. Let's get into it.


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Avery, cast your mind back. In 2008,


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astronomers directly imaged a planet


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around the young star Beta Ptorus, one


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of the very first exoplanets ever


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photographed. That was Beta Pictorius B.


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A second planet C followed and ever


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since there's been a nagging suspicion


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that the system was hiding something


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more


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>> because of the disc, right? Beta Pctorus


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has this magnificent debris disc. It's


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the poster child for planet formation.


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And parts of it were warped and sculpted


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in ways that two known planets couldn't


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fully explain.


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>> Exactly. And now we know why. In a study


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published Wednesday in the Astrophysical


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Journal Letters, a team using the


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European Southern Observatory's Very


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Large Telescope in Chile has confirmed a


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third planet, Beta Pictorius D. And


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here's the headline stat. It's roughly


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100 times fainter than Beta Pictorius B,


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which makes it the faintest exoplanet


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ever directly imaged from Earth. 100


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times fainter. To put that in context


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for everyone, direct imaging means


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actually capturing the planet's own


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light in a photograph next to a star


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that's overwhelmingly brighter. It's


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often compared to spotting a firefly


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next to a lighthouse. This is spotting a


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very dim firefly. And the discovery


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itself was serendipitous. Ben Sutliff at


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the University of Edinburgh, who co-led


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the study, said they were originally


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just going back to study the known


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planet Beta Pictorius B to see how it


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changed over time. But in their new


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images from the VLT's AIS instrument,


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there was something else, a faint point


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of light separated from planet B that


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sent them down an entirely new path.


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>> And this is where the hideand seek comes


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in. Once they knew what to look for,


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they trled back through the archives and


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there it was, lurking in more than a


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decade of old observations from the VT


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sphere instrument. And even in James


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Webb's space telescope data, the planet


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had been photographed for years. Nobody


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had noticed.


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>> Co-author Jane Burkeby at Oxford put it


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beautifully. Planet D has been playing


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hideand seek with us for over a decade.


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And now we can say, "Found you." So,


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what do we know about the world itself?


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>> It's a gas giant about 2.4 times the


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mass of Jupiter, which sounds big, but


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is actually the lightweight of the


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family. Planets B and C are each 10


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Jupiter masses. Planet D sits much


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further out from the star on a wide


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orbit, so it's cooler and dimmer than


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its siblings, hence the difficulty. And


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satisfyingly, its presence helps explain


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that odd structure in the debris disc


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that's puzzled astronomers for years.


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>> There's also a nice milestone tucked in


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here. This makes Beta Ptorus only the


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second planetary system after HR8799


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where more than two planets have been


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directly imaged. We're building up


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actual family portraits of other solar


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systems. now


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>> and an independent team at the


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University of California spotted the


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same object in her own data at almost


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the same time which gives the detection


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real confidence. Now the bit our


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audience will love Beta Ptorus is a


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southern star. It sits in the


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constellation Pictor the painters easel


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just next to Brilliant Canopus and at 63


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lighty years away it's visible from


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Australia and New Zealand. Though right


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now in July, it's low in our evening sky


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and best hunted in the pre-dawn hours


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later in the year.


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>> A planetary system with three


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photographed worlds sitting in our


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southern sky. Not bad at all. Next, a n


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a project 9 years in the making has just


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crossed the finish line. The US National


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Science Foundation's National Radio


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Astronomy Observatory has announced that


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observations for the Very Large Array


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Sky Survey, VLAS, are complete. It's the


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most detailed radio survey of the sky


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ever conducted.


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>> This is the VA in New Mexico, the iconic


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Y-shaped array of 27 dishes from every


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space documentary ever made.


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>> That's the one. From September 2017


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through February this year, the array


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repeatedly swept about 34,000 square


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degrees. Essentially, the whole sky


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visible from New Mexico. Everything


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north of -40° declination. That's


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roughly 80% of the entire celestial


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sphere mapped at a resolution of about 2


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1/2 arcseconds in the 2 to 4 GHz band.


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>> And how does that compare to what came


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before? It's about 18 times sharper than


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the previous benchmark all sky radio


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survey from the 1990s. The numbers are


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staggering, roughly 6 1/2,000 observing


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hours, half a pabyte of raw data, and


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the processed data products are expected


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to reach around 2 pabytes, the largest


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data volume the VA has ever produced.


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They use a clever on the-fly mosaicing


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technique where the antennas sweep


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continuously across the sky in a raster


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pattern rather than stopping to point at


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each field.


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>> And crucially, they surveyed the sky


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multiple times over those nine years,


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which means Vlass isn't just a map, it's


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a movie. Comparing epochs revealed a


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dynamic radio sky sources that flare,


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fade, or appear from nowhere. exploding


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stars, feeding black holes, colliding


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neutron stars.


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>> Which brings us to the timing. And


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honestly, the timing is the best part of


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the story. Just over 2 weeks ago, on


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June 30th, the Vera C. Rubin Observatory


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in Chile began its decadel long legacy


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survey of space and time, sweeping the


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southern optical sky every few nights.


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So for the first time in history, we


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have a complete highresolution radio map


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and a real-time optical transient stream


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operating simultaneously.


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>> Though when Reuben flags something going


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bang in the optical, astronomers can


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immediately check what that patch of sky


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looks like and looked like in the radio.


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The whole multi-wavelength discovery


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machine the community has spent two


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decades building is now switched on


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>> and the data is public. Radio


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astronomers, multi-wavelength folks,


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citizen scientists, the radio sky now


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belongs to everyone.


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>> Now to a decades old mystery that may


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finally have its answer, Avery. How do


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super massive black holes keep feeding?


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Nearly every large galaxy hosts one of


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these monsters. Millions or billions of


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times the mass of the sun. When they


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feed, they blast out enormous energy,


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powerful jets that heat the gas around


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them. And that's the paradox. That


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heating should cut off the black hole's


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own fuel supply. So why don't they


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starve?


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>> The leading idea has been a kind of


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cosmic recycling loop. The heated gas


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eventually cools back down, condenses


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into long, thin streamers called


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filaments and rains back towards the


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center, self-regulating. But actually


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seeing the connection filament to black


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hole has eluded astronomers for decades


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>> until now. An international team led by


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Julia Havlassa Laurando at the


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University of Montreal pointed the James


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Webb Space Telescope at NGC 4696,


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the giant elliptical galaxy at the heart


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of the Centurus cluster about 145


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million lighty years away. Their results


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were published this week in the


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astrophysical journal Letters.


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>> And Centurus, we should note, is a


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southern constellation. This galaxy


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cluster rides high in our winter sky


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right now, though you'll need a decent


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telescope for the galaxy itself.


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>> Right. Now, Hubble had previously


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photographed a curious S-shaped swirl of


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gas near this galaxy's central black


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hole. But Hubble could only show where


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the gas sat, not how it moved. So the


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team gave Web's NISP instrument nearly 8


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hours on the target and mapped the


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motion of the gas deep inside the black


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hole sphere of influence, resolving


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features just 30 light years across in a


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galaxy hundreds of thousands of


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light-years wide. And the swirl turned


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out to be


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>> a spinning disc of gas wrapped around


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the black hole nearly 800 lightyears


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across with material whipping around at


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up to 600 km per second. And here's the


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money shot. That disc is physically


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connected to one of the huge infalling


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filaments stretching out into the


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galaxy. They watched gas flowing along


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the filament pouring into the disc and


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from the disc falling onto the black


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hole.


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>> The missing link caught on camera. Heat


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the gas. The gas cools into filaments.


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The filaments feed the disc. The disc


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feeds the black hole. The black hole


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heats the gas. Round and round it goes.


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>> Pavlocondo said web is revealing that


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black holes might be the ultimate cosmic


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recyclers. And because this feeding loop


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shapes when galaxies can and can't form


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stars, understanding it is really


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understanding how galaxies, including


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ours, grow up.


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>> Anna, time for a double bill from the


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outer solar system. Two stories, one


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spacecraft, and a dwarf planet that


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keeps on giving. First, scientists have


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detected landslides on Pluto for the


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very first time.


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>> This is New Horizon's data, isn't it?


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That flyby was 11 years ago this week.


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>> It is. And that's the delightful part. A


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paper in the journal Icorus, which has


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been making headlines this week, reports


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that an international team went back


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through the highresolution images from


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New Horizon's Lori camera. Pictures


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showing Pluto's surface at about 300 m


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per pixel and found six large landslides


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inside three impact craters near Sputnik


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Planita, that famous heart-shaped


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nitrogen ice plane. How do you recognize


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a landslide on a world made of ice?


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>> Same fingerprints as Earth.


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Crescent-shaped collapse scars near the


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crater rims, huge displaced blocks of


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ice, and debris fanning out across the


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crater floors. The team measured them.


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These slides descend 1 12 to over 2 km


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run out as far as 14 1/2 km, and the


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largest covers around the 130 km.


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>> And landslides are everywhere else,


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aren't they? Earth, Mars, series,


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asteroids. Even Pluto's moon, Sharon,


00:11:53.440 --> 00:11:55.829
showed evidence years ago. Pluto itself


00:11:55.839 --> 00:11:57.269
was the odd one out,


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>> which was genuinely puzzling because


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Pluto has steep crater walls and rugged


00:12:01.680 --> 00:12:04.310
icy terrain. All the right ingredients.


00:12:04.320 --> 00:12:06.550
Now, the gap is filled, and it tells us


00:12:06.560 --> 00:12:08.629
gravity-driven slope processes are


00:12:08.639 --> 00:12:10.710
actively reshaping Pluto's frozen


00:12:10.720 --> 00:12:13.269
surface, even under gravity a fraction


00:12:13.279 --> 00:12:15.509
of ours. What triggered them is still


00:12:15.519 --> 00:12:17.750
open. Possibilities range from tectonic


00:12:17.760 --> 00:12:19.990
activity to meteoroid impacts.


00:12:20.000 --> 00:12:22.389
>> A world we visited for a few hours in


00:12:22.399 --> 00:12:25.430
2015 still handing us firsts a decade


00:12:25.440 --> 00:12:26.310
later.


00:12:26.320 --> 00:12:29.030
>> And it's not done because part two of


00:12:29.040 --> 00:12:31.829
our Pluto double is about the other half


00:12:31.839 --> 00:12:33.430
of that famous pair.


00:12:33.440 --> 00:12:36.230
>> Jiren Pluto's enormous moon so big


00:12:36.240 --> 00:12:38.230
relative to Pluto that the two really


00:12:38.240 --> 00:12:40.629
form a double world. And a study


00:12:40.639 --> 00:12:42.230
published Tuesday in Nature


00:12:42.240 --> 00:12:44.790
Communications says Sharon's mountains


00:12:44.800 --> 00:12:47.110
have preserved a memory of a wilder


00:12:47.120 --> 00:12:47.829
youth.


00:12:47.839 --> 00:12:49.269
>> What kind of memory?


00:12:49.279 --> 00:12:52.150
>> A record of despinning across the solar


00:12:52.160 --> 00:12:54.710
system. Tidal forces gradually slow a


00:12:54.720 --> 00:12:57.829
body's rotation. And as the spin slows,


00:12:57.839 --> 00:13:00.790
the body's shape relaxes, stressing and


00:13:00.800 --> 00:13:02.949
cracking the surface. It's long been


00:13:02.959 --> 00:13:05.030
theorized for Sharon, but clear


00:13:05.040 --> 00:13:07.509
geological evidence was missing. So


00:13:07.519 --> 00:13:10.629
Hanzang Chin and colleagues at ETH Zoric


00:13:10.639 --> 00:13:13.910
and UCLA examined the orientations and


00:13:13.920 --> 00:13:16.310
types of tectonic features, mountain


00:13:16.320 --> 00:13:19.509
ranges and faults in Oz Terra, Sharon's


00:13:19.519 --> 00:13:22.150
northern rugged highlands. Again, using


00:13:22.160 --> 00:13:24.310
New Horizon's flyby data,


00:13:24.320 --> 00:13:26.230
>> and the tectonic pattern fits the


00:13:26.240 --> 00:13:27.430
despinning story


00:13:27.440 --> 00:13:29.590
>> beautifully. Their modeling suggests


00:13:29.600 --> 00:13:32.150
Sharon's rotation period was once around


00:13:32.160 --> 00:13:35.430
14.3 hours and it has since slowed to


00:13:35.440 --> 00:13:38.710
today's roughly 153 hours, locked in


00:13:38.720 --> 00:13:41.350
step with its orbit around Pluto. That's


00:13:41.360 --> 00:13:43.670
more than a 10-fold slowdown, and the


00:13:43.680 --> 00:13:45.670
stresses from that transformation are


00:13:45.680 --> 00:13:47.110
etched into the mountains we


00:13:47.120 --> 00:13:48.790
photographed in 2015.


00:13:48.800 --> 00:13:51.030
>> Chen said the study drastically changed


00:13:51.040 --> 00:13:53.269
her understanding of Cheron's geological


00:13:53.279 --> 00:13:55.350
history. And there's a bonus finding,


00:13:55.360 --> 00:13:57.910
isn't there, about how Cheron was born.


00:13:57.920 --> 00:14:00.470
Yes, the way despinning and global


00:14:00.480 --> 00:14:03.030
contraction evolved together favors


00:14:03.040 --> 00:14:05.750
what's called a cold start for Sharon,


00:14:05.760 --> 00:14:07.750
which is a real clue to the early


00:14:07.760 --> 00:14:10.230
thermal history of icy moons across the


00:14:10.240 --> 00:14:12.949
outer solar system. So, between Pluto's


00:14:12.959 --> 00:14:15.670
landslides and Sharon's slowing spin,


00:14:15.680 --> 00:14:18.150
one 11-year-old data set gave us two


00:14:18.160 --> 00:14:20.629
papers in a week. Not a bad return on a


00:14:20.639 --> 00:14:21.350
flyby.


00:14:21.360 --> 00:14:23.910
>> Our final story today, Anna, comes with


00:14:23.920 --> 00:14:26.949
some genuinely eyewidening numbers.


00:14:26.959 --> 00:14:29.670
SpaceX has filed its latest semiannual


00:14:29.680 --> 00:14:32.389
constellation status report with the US


00:14:32.399 --> 00:14:34.629
Federal Communications Commission. And


00:14:34.639 --> 00:14:36.790
according to coverage of the filing,


00:14:36.800 --> 00:14:42.310
Starling satellites performed 27,152


00:14:42.320 --> 00:14:44.550
collision avoidance maneuvers between


00:14:44.560 --> 00:14:48.550
December 2025 and May 2026.


00:14:48.560 --> 00:14:50.550
>> 207,000


00:14:50.560 --> 00:14:51.990
in 6 months.


00:14:52.000 --> 00:14:54.790
>> Up nearly 60,000 on the previous half


00:14:54.800 --> 00:14:57.509
year. Put the two periods together and


00:14:57.519 --> 00:15:01.350
the constellation made over 355,000


00:15:01.360 --> 00:15:04.150
dodges in 12 months, more than triple


00:15:04.160 --> 00:15:07.829
what it performed in all of 2024. At on


00:15:07.839 --> 00:15:10.550
average, each Starling satellite now


00:15:10.560 --> 00:15:13.350
swerves more than 40 times a year.


00:15:13.360 --> 00:15:15.750
That's nearly a dodge a week per


00:15:15.760 --> 00:15:16.629
satellite.


00:15:16.639 --> 00:15:18.710
>> Let's be fair to SpaceX for a moment,


00:15:18.720 --> 00:15:20.949
though. These maneuvers are the system


00:15:20.959 --> 00:15:22.870
working as designed, aren't they?


00:15:22.880 --> 00:15:24.949
>> They are. The satellites dodge


00:15:24.959 --> 00:15:27.189
autonomously whenever the predicted


00:15:27.199 --> 00:15:29.990
collision probability exceeds 3 in 10


00:15:30.000 --> 00:15:32.389
million, an extremely conservative


00:15:32.399 --> 00:15:34.710
threshold, far tighter than the industry


00:15:34.720 --> 00:15:37.590
standard. Experts consistently credit


00:15:37.600 --> 00:15:40.069
SpaceX with managing its traffic well


00:15:40.079 --> 00:15:42.790
and being transparent with the data. The


00:15:42.800 --> 00:15:44.949
concern is the trend line, not the


00:15:44.959 --> 00:15:46.870
competence. because the numbers


00:15:46.880 --> 00:15:49.430
compound. More satellites means more


00:15:49.440 --> 00:15:51.910
close approaches means more maneuvers


00:15:51.920 --> 00:15:54.230
means more residual risk that never


00:15:54.240 --> 00:15:55.829
quite goes to zero.


00:15:55.839 --> 00:15:58.470
>> Exactly the point Hugh Lewis makes. He's


00:15:58.480 --> 00:15:59.910
the University of Birmingham


00:15:59.920 --> 00:16:01.990
astronautics professor who's tracked


00:16:02.000 --> 00:16:04.550
these reports for years. Each maneuver


00:16:04.560 --> 00:16:07.110
cuts the collision odds to about 1 in a


00:16:07.120 --> 00:16:09.829
million, which sounds negligible, but as


00:16:09.839 --> 00:16:11.910
he puts it, if you make a million


00:16:11.920 --> 00:16:13.590
maneuvers with a 1 in a million


00:16:13.600 --> 00:16:16.069
residual, you end up with an aggregate


00:16:16.079 --> 00:16:18.389
risk across the constellation that you


00:16:18.399 --> 00:16:20.949
simply can't get rid of. His blunt


00:16:20.959 --> 00:16:22.790
assessment, he thinks we're heading


00:16:22.800 --> 00:16:24.949
towards a situation where there will be


00:16:24.959 --> 00:16:27.269
a collision involving an operational


00:16:27.279 --> 00:16:29.829
satellite in the constellation. And the


00:16:29.839 --> 00:16:31.189
projections


00:16:31.199 --> 00:16:33.910
>> on current growth, Starlink passes a


00:16:33.920 --> 00:16:36.389
million total avoidance maneuvers by mid


00:16:36.399 --> 00:16:39.670
2027. And by 2030, the constellation


00:16:39.680 --> 00:16:41.269
could be making more than a million


00:16:41.279 --> 00:16:44.230
maneuvers every single year. Remember


00:16:44.240 --> 00:16:47.269
too, and regular listeners will, SpaceX


00:16:47.279 --> 00:16:49.749
has applied to the FCC to grow Starlink


00:16:49.759 --> 00:16:52.710
toward a 100,000 satellites, a story we


00:16:52.720 --> 00:16:54.870
covered a couple of weeks back. And it's


00:16:54.880 --> 00:16:56.629
not alone up there. Amazon's


00:16:56.639 --> 00:16:59.110
constellation and China's Ken Fan are


00:16:59.120 --> 00:17:00.949
actively deploying as well.


00:17:00.959 --> 00:17:03.030
>> The number of operational spacecraft in


00:17:03.040 --> 00:17:05.189
orbit has gone from about 10,000 to


00:17:05.199 --> 00:17:08.390
about 16,000 in just a year. Other


00:17:08.400 --> 00:17:10.230
experts are calling for operators to


00:17:10.240 --> 00:17:12.309
disclose predicted maneuver counts


00:17:12.319 --> 00:17:15.029
before constellations are even approved.


00:17:15.039 --> 00:17:16.549
Though regulators know whether the


00:17:16.559 --> 00:17:18.789
satellites can actually keep up.


00:17:18.799 --> 00:17:21.189
>> Low Earth orbit is a shared resource.


00:17:21.199 --> 00:17:23.350
And this is the traffic report. We'll


00:17:23.360 --> 00:17:24.949
keep watching the numbers because


00:17:24.959 --> 00:17:27.350
everyone from astronomers to airlines to


00:17:27.360 --> 00:17:29.909
your GPS depends on that neighborhood


00:17:29.919 --> 00:17:31.110
staying safe.


00:17:31.120 --> 00:17:33.430
>> Time now for tonight's sky watching. And


00:17:33.440 --> 00:17:35.430
for our southern hemisphere friends, the


00:17:35.440 --> 00:17:37.669
news is good. The moon is a waning


00:17:37.679 --> 00:17:39.990
crescent rising in the small hours. So


00:17:40.000 --> 00:17:41.669
evenings this week are dark and


00:17:41.679 --> 00:17:42.950
glorious.


00:17:42.960 --> 00:17:45.350
>> Which means the winter Milky Way at its


00:17:45.360 --> 00:17:47.990
absolute best. Face south after dinner


00:17:48.000 --> 00:17:50.310
and the galactic core in Sagittarius and


00:17:50.320 --> 00:17:52.870
Scorpius is almost directly overhead


00:17:52.880 --> 00:17:55.190
from most of Australia and New Zealand.


00:17:55.200 --> 00:17:58.150
Dust lanes, star clouds, the lot. If you


00:17:58.160 --> 00:18:00.230
can get away from city lights this week,


00:18:00.240 --> 00:18:01.110
do it.


00:18:01.120 --> 00:18:03.029
>> While you're there, sweep up Omega


00:18:03.039 --> 00:18:05.029
Centauri and the Southern Cross riding


00:18:05.039 --> 00:18:07.510
high. And if you've got binoculars, the


00:18:07.520 --> 00:18:09.669
starfields between Scorpius's tail and


00:18:09.679 --> 00:18:12.070
the teapot of Sagittarius will keep you


00:18:12.080 --> 00:18:14.870
busy all evening. Saturn is climbing in


00:18:14.880 --> 00:18:16.870
the east by mid evening for a late night


00:18:16.880 --> 00:18:19.350
treat. And dazzling Venus still rules


00:18:19.360 --> 00:18:21.669
the early evening western sky.


00:18:21.679 --> 00:18:23.669
>> And one for the launch watchers.


00:18:23.679 --> 00:18:26.950
SpaceX's Starship Flight 13 window opens


00:18:26.960 --> 00:18:29.270
tonight, US time. That's tomorrow


00:18:29.280 --> 00:18:33.350
morning for us from about 8:45 AEST. So


00:18:33.360 --> 00:18:35.430
pour a coffee and watch this space.


00:18:35.440 --> 00:18:37.430
We'll have the full story in Saturday's


00:18:37.440 --> 00:18:38.630
weekend rap.


00:18:38.640 --> 00:18:40.470
>> That's it for today's episode. Thanks


00:18:40.480 --> 00:18:42.710
for joining us. You can find show notes,


00:18:42.720 --> 00:18:44.710
links to every story, and our back


00:18:44.720 --> 00:18:47.669
catalog at astronomydaily.io.


00:18:47.679 --> 00:18:50.310
And we're astronomyaily pod on all the


00:18:50.320 --> 00:18:51.350
socials.


00:18:51.360 --> 00:18:53.990
>> Astronomy Daily is part of the byes.com


00:18:54.000 --> 00:18:56.070
podcast network. I'm Avery


00:18:56.080 --> 00:18:58.150
>> and I'm Anna. We'll see you tomorrow.


00:18:58.160 --> 00:18:59.350
Until then,


00:18:59.360 --> 00:19:11.669
>> clear skies.


00:19:11.679 --> 00:19:15.480
Stories told.